One can never have enough bench block styles. Small tasks, difficult tasks, protecting the gun art while installing / removing pins is the gunsmithing craftsmanship! Wood, polymer, hardened steel, aluminum, brass, lead blocks.
I have sourced some free! (in the spirit of this thread) wood tile floor samples from the big box store for fabricating a block.
What I dislike about wood & polymers is that the devices themselves absorb ,and thus divert the energy of a punch, that is intended for the object of the task, removing / installing said pin!
I have used a variety of brass plumbing hardware and Grade 8 bolts as adjustable height bench blocks (kind-of -like a machinist screw jack on the mill). Their small profiles, protected with painters tape, are pretty handy for many tasks, one in particular is installing / removing AR trigger guard roll pins without fracturing the "ears" of the trigger guard.
A few aluminum disks with various mortise profiles including recess for fitting in the bench vise.
For myself, I prefer the stiffer non-marring Delrin block v. the Brownell's styled softer polymer blocks that "bounce" the energy about on impact.
The lead blocks are old-school but seem to be really handy, particularly the longer flat block that supports a long flat side of a firearm.
The large flat lead block is what is used for construction of the walls inside a radiology imaging center.
Other lead block profiles sourced from the bait & tackle shop!
Probably not used in California.
Finally, some "reverse" style bench blocks that hold the roll pin for installation when using a small roll-pin holder
can be awkward in some firearm geometries.