I found S&W Diesels in Wilmimgton to be much more affordable including
shipping and faster than the Bay Area
Perkins dealers. Solder will probably last until it forms another pinhole somewhere else.
Carl at Nelson Yahcts had a whole 4.107 to sell really
cheap, it had been submerged in fresh
water. If you want other extra
parts it might be worth it and you could have that FI line cleaned at a radiator shop, it would be almost as good as new.