Do you recognize this sedimenter? It's from my '79 Series III Santana. While troubleshooting a starting problem I discovered the cap & stem on the ground beneath my truck (the bolt had sheared off). I'm looking for a replacement, but this part doesn't look the same as the diagrams & pictures that I've seen for British-built Series IIIs. Is there a source for this? Is it interchangeable with a British-built part?