or, if you reload, round up some .45 auto rim brass. many of us with M25s do this. works like any other rimmed round. cuts the bother of clips or punching out empties one at a time.
i have no idea what a box of .45AR would cost, even if you could find it, but, would expect it to be high due to lack of demand. maybe/maybe not. dunno. i handload, so, dont keep up with prices of "storebought".
tell you this - you got a nice gun.
mine is blue and .45C. keep looking at stainless, but.....my blue guns don't usually go outside in rough weather, i have stainless in magnums for that.
decades ago, i had an M25 in .45ACP, then they came out with the .45C version. so, it was off with the old and on with the new. the stainless had not been produced at that time or i would have one. my blue gun is an old friend now so is staying around if in the back seat to the magnums. it still gets shot regularly due to it's looks and accuracy.
good shooting with your 625