I just posted about theses in the '3D Printed Modified' build thread, and I realize I should post here since these are available...
These are 3D printed 'Wide-5' wheel inserts that fit the common Pro-Track (1/2" hub) wheel/tire.
3D PRINTED 'WIDE-5' WHEEL INSERTS 1/2" HUB-
This is just a camera phone pic, but you can still make out the wheel detail is fairly resolved. Comparing the lug nut/studs to a fingerprint ridge in the pic offers a sense of detail. This is an unpainted rear wheel insert, and has eight (8) bolts on it's bearing hub cover.
3D PRINTED 'WIDE-5' FRONT WHEEL INSERT IN A PRO TRACK WHEEL-
This is a front insert, with a little paint and sitting in a used Pro Track rim I had laying around. The front insert has four (4) bolts on it's bearing hub cover.
3D PRINTED WHEEL INSERTS FROM NYMODIFIEDS.COM-
These are 3D printed hubs and not resin cast. They are available in packages of four (4 = two front + two rear). They are sized to fit the Pro Track hub and would look great on any of the nymodifieds.com cars or any others that you may run using the fairly common 1/2" hub.
I really have to get around to updating the website to include some of the newer pieces that are available - but early adopters can contact nymodifieds.com for these.