Need help identifying a RUUD condenser dual-run capacitor

I need to replace a 31 year old condenser dual-run capacitor in a RUUD air conditioner (model UALA-036JAS). Unfortunately the existing capacitor has absolutely no markings on it. When checked with a Supco capacitor tester it reads "open" on all connections. I called RUUD/Rheem and they specified a 40/5 uF replacement. I contacted Bristol who makes the compressor (but has been bought and moved to Thailand) and they spec'd a 35/5 uF.

Obviously I don’t want to install the wrong one, so any help or thoughts on this would be greatly appreciated! -Steve