Sad but true. I try to go with off-the-shelf whenever possible. Knew a guy who built himself a street rod and liked the looks of a set of Packard motor mounts he had on the shelf, so he ran them... and when he needed new ones, he discovered he had the only set on the west coast.
While it's good to maintain original for restoration purposes; for a daily driver, it's sure nice to just swing by the local NAPA store to keep yourself up and running.