old prodive spg flanged spool valve ?

[idive2]

I dug out an old spg while my other spg and hoses are put away while newer reg in for service.
This spg has a spool valve with a flange right in the center of the spool valve. Maybe keeping it
centered properly. I had some newer style spool valves and tried to use it today on a back-up reg
and had a small steady flow of air bubbles from the spg. I guess I could search to see if this flanged
spool valve is still available or maybe just swap out the o-rings as the valve still looks to be in fair shape.
Anyone have any experience with these or know how far back this style was used ?

[Fishpie]

Probably just the o rings.
The main compatibility problem is usually with the waisted spools with a long and a short end.

[idive2]

Yeah, I removed the spg and found the o-ring was rolled back out of the groove. It may be that
the newer spool valve goes further into the valve and perhaps hung up on a surface that has been
unused with the shorter spool valve. Put the old one back in and seems to be okay. Just wondered if maybe
the collar or flange might be necessary to keep spool valve in correct location. The newer ones probably
have a predetermined measurement that the valve sits in. Maybe these old ones need the flange to keep it
centered ? This spg looks like it may be from the 70's or so. I'm going to do a little more searching, I'm curious what
era it was from. Does not look like the vintage stuff but maybe a bit after some of the very early stuff.