Check this site out for mechanical retracts for the .40 size Corsairs (I think they are on page 7, won't show a picture). Wing Manufacturing had a set at their booth in Toledo and were kind enough to send the info to me. They looked great in their (Wing Mfg) .40 Corsair and could even be fitted to the GP Corsair (ugh! flat sided fuselage). Much sturdier than the Hobbico set and are only $25.00.

PS: The owner of KMP told me he would sell me the .60 size retracts and even quoted a price. He told me he was ordering a new batch from overseas. Since it looked like retrofit would be quite a bit of work I did not purchase them but plan to build a new plane and incorporate these retracts.