FYI: U-77 audio connectors cheap.
 

Baran's Surplus (Steve and John) have a quantity of cutoff U-77
old-family audio plugs for a buck each. These guys are a very reliable
East-Coast (PA) surplus supplier. I have no affiliation with them and
just wanted to pass on the info. The buy-it-now auction at $1 each is
150051941409 or search for "U-77/U cutoff". Shipping for my 25 of them
was $15. Maybe that's a bit on the high side but its still less that $2
each. There were 75 left as of this a.m. Again, just passing the
info.......... Jeep/K3HVG