I think the OP is wanting to just go in a gun shop and get a small break off the suggested retail and get one of those new J frames with a lock. It's easy . . . but expensive for what you get.
However, I'd strongly recommend that he start looking for a pristine USED J frame from back in S&W glory days . . . with a pinned barrel, real wood stocks that are fitted and individually serial numbered to the gun.
They ARE out there! Many were bought by middle aged original owners in the early and late '60s as "nightstand guns." True to their purpose, their owners bought a box of ammo . . . shot part of that box at the range to get umm . . . "familiar" with the gun . . . then they cleaned it and put it in the nightstand.
FAST FORWARD FIFTY YEARS . . .
Aunt Tillie is selling off her deceased husband's things before going into the nursing home, or possibly she's selling Uncle Bob's nightstand gun now that he's gone. She goes into the local gunshop anywhere in America and is pleased to be offered $125 bucks for that "old gun" by the gunshop. The owner even tells her that's MORE than Uncle Bob PAID for in in 1964!!!
She sells it . . . and the gun shop puts it in their SAFE, NOT in their sales counter . . . to wait on a serious buyer to come in wanting an NICE, vintage S&W J-frame!
TO THE ORIGINAL POSTER . . .
Go into your local shops and meet the owners. Tell them you are looking for a pristine, vintage S&W J-frame. Don't be picky about model right now, for ANY are great guns! Once the owner realizes you aren't just a tire kicker, the guns will start coming out of the safe! SEASONED GUN OWNERS KNOW THIS FACT . . . BUT YOU DON'T YET.
Here's one I picked up a couple of years ago for $350, with only the slightest turn line on the cylinder. It was a widow's 2nd husband's nightstand gun. She outlived three husbands and it was time to sell the little Smith. Another local gunshop was asking $850 for a new "Classic" series Model 36 "just like it" . . . but the new gun had the damn lock, cheesy "fancy" computer-cut wood grips, a poorer polished nickel finish and no pinned barrel.
Hmmm . . . instead of getting a new paperweight at a high price, I spent half as much for a much more desirable gun (to those who know and collect guns).
Here's the gun . . . which is now worth about $75 more on the market than I paid for it . . . though I'll never sell it. I DO shoot it sometimes though, and it is wonderfully accurate with an incredible trigger.
I'd recommend you save money and get something nice and desirable too.
BTW . . .
1. The pinned barrel instantly tells those in the know that this gun was made before S&W stopped pinning the barrels in 1982.
2. The original wood grips are called "diamonds" for an obvious reason. Diamonds tell knowledgeable gun lovers that the gun was made before Smith started saving money by not using the diamond on their grips in 1968. By heart starts beating faster when I see a nice "diamond" in the display counter. If I like the gun I ask to remove the right grip to see if the number on the inside of the grip matches the gun's number before I buy it! It makes the gun worth more!!!
3. The "square" cylinder release latch was phased out in in 1966. My heart beats even faster when I see a J frame with diamonds AND the square latch!!!
This one? Turns out it was made in 1964 . . . and I'll take one of these any day over the new stuff the factory turns out today!!!
SHOOTS GREAT TOO . . . as you'll see . . .
On top of an LP record from the same era, on the day I bought it . . .
It's first target shot by me . . . all five shots into about a 1" group DEAD PERFECT into a black 1" square I was aiming at. Distance: 10 YARDS, standing with no support as I shot it! Accurate "Roscoe" indeed!
NO "RUBBERS" ON THIS BABY . . .
I tried 'em for "comfort" but found the original wood grips were perfect and very comfortable, when I added a Tyler T-grip. The Tylers are still made and those in the know back in the day usually used 'em for very good reason!!!
And here she is in a Rosen UPL holster . . . a really nice "square latch" deserves a great holster! . . . BEST OF ALL . . . I've got less than $450 in the entire outfit!
Look a little, ask around, and you can do better than new for less too . . . and have a gun that knowledgeable gun owners will come over to see when you are plinking at the range!