What you are asking is not possible, as every driver has unique Thiel/Small parameters. This is especially critical for passive radiator designs. The passive radiator also has T/S parameters. There are few passive radiators available.
Your best bet is to see if an outfit like Orange County speakers can rebuild your drivers to original specification. If not you are out of options. With speakers this age, this is a long shot.
In any event why do you feel reconing will not solve the problem? If the cone and voice coils are OK, then refoaming will do the trick.