another quick-n-dirty to support scope side rail rivet head from the inside of the receiver. recreator has his own version but i got mine for a cost of $0 and and 1 hour of my time.
very simplistic. can be made with just hand tools:
-hand drill
-center punch
-hacksaw (or angle grinder with cut off disk)
-files (optional to make it purty)
-5/16" ball-nose endmill for the dimple, 1/4" tends to be a bit small for the commonly available rivet heads
probably longer than an hour if you're sawing by hand, but if you got tools use them if not - still doable. although if you have to buy one tool for this then angle grinder would be best choice. they are cheap $20 at HF plus the disks.
I used a piece of a 1"x2" mild steel flat bar i had laying around. if you have to order it online then you are probably cutting it pretty close to a price of recreator tool.
if someone want dimensions, please reply below, unless i already did it, then never mind 😉