The guy at the l ink below offers, or at least used to offer a nice replacement. His email is below as well when I asked about it in July of last year...

gearbox Puma, 1:16 gearing, hardened steel gears, bearings, motor Absima 55T 7700 RPM or 50T 8300 RPM, complete w/ drive shaft. Very powerful, high precision, smooth running construction. Modification on chassis required. See picture.
Available in 2-4 weeks. € 229.- plus shipping.

http://www.modellspiegel.com

I didn't get it, but am still considering it despite the price. His gearboxes are really nice looking.

PS metal origin has a 222.coming out...saw some videos, looks nice....lol