Using a Schick Proline B-20 blade in a Pal Injector Razor

I recently purchased a Pal Adjustable Razor on eBay, that came with the original case and blades.  Those blades unfortunately had degraded with age.  So I bought 4 packs of Schick Proline B-20 blades at a bargain price off Obie on BS&T.  The B-20 blades however do not come with an injector key, so a little ingenuity was required.  First I unloaded a new Proline blade from the package.  Then drawing back the blade loader on the old injector, I depressed the top blade with a chop stick and started inserting the new blade on top of the old one.  I then used a small screwdriver to hold it in place while I pushed it in the rest of the way.  With that done, I used the old (1962?) injector to inject the new blade.  It worked, but the action wasn't smooth.  I think the old injector mechanism might be a little compromised by rust.  I'll try out the razor in the morning.  But I'm looking for an empty injector that's a little bit newer for the future.  I'll be happy to pay the postage.