It must have been more than 10+ years ago I put this together - I don't remember any easily available ready to go ones from back then. Had my knowledge of plumbing fittings been better I might have done it straight off the pf can't really remember why it was done this way! [EDIT: the stock Rancilio pf at that time had a notch in the pf body itself that prevented a complete seal at the spout knew there was a reason]
Nice use of blanking plate, I had no idea what you'd come up with. I don't have one for a gaggia I'm afraid but tbh as suggested the bits are so cheap nowadays it's hardly worth the cost of sending or you could ask on coffeeforumUK.