M1A2 Abrams

All I have for silicon is some super stiff stuff that sets up quickly, but I';ve only got 2 in my Dragon kit, and I'd like to have a couple more, so I'm thinking of trying it out, if it works, I can cast copies and might be able to send some your way.  If you can cover shipping costs.  Not worried about the cost of resin as it's such a minute amount to make a few road wheels.  Assuming the hubless version?

As stik said, get the Tamiya older Modern US Accessory set.  It has a couple roadwheels and a bunch of other gear, mostly '80-'90s stuff though.  

If you want more modern gear, get their newer Modern US Military Equipment set.  It has current gear (as of about 2005) and current MRE boxes. 

Am looking for spares to put on the turret along with other equipment, that I have

If you are looking for spare roadwheels for an M1, the original Tamiya Modern Accessory set came with a few. Along with the older style track shoes, and M48/M60 roadwheels and late style track shoes and pads, and other goodies. That set was re issued not too long ago with the addition of some ICM US late  Cold War Infantry figures.

Sorry, I don't know of any AM road wheels for any Abrams.  What is wrong with the ones that came with your kit?