Dave, You have some choices. Antique Electronic Supply and Surplus
Sales of Nebraska both offer said-to-be-new can-type electrolytics at
very high (relatively speaking) prices. If below the chassis esthetics
are of less importance, leave the cans in place and wire around them
using an appropriate value replacement, one typical brand being
axial-lead XICONs. Mouser has the best price on these. Also available
are "snap-in" type computer caps. No leads on these, of course, just
tabs. The third possibility is to remove the offending can capacitor,
gut it and re-stuff with one of the new, smaller types. Personally, I
below chassis wire in XICONs. But, it all depends on what your pleasure
is. de Jeep/K3HVG

Dave wrote:
I'm starting my first refurbishment of an old receiver.

Even before I power up I want to replace the electrolytics based on age
degradation principles. [I'm a retired EE and understand age degradation
in 40+ year old capacitors]].

Being away from parts suppliers for 10+ years leaves me ignorant of what
is where. Therefore my original question: "What is a good source for
electrolytics?"]

/S/ DD, W1MCE