Vintage Double Hose

I now have a goodly number of 1/2" valves and manifolds that use the old "lead bullet" burst discs. Problem is hardly anyone will fill a tank with this type of valve.
The burst disk plugs in old Dacor valves look like they might work, but are they rated too high to use in a 2150 or 2250 psi tank? I remember reading somewhere the lead bullet ones are rated at 3200 psi, but don't know what the Dacor plug's rating is. Can anyone shed light on this, or at least know where conversions might be found?

I regularly see three different sizes of burst disk and can get them for most pressures. 3/8" is the most common I have or can get them for 1800, 2250, 2400, 3000, 3300 and 3500. I believe that most of the lead plug burst disks or 3/8". I also have 1/2" in most pressures. The 3/8" are three part assemblies and the 1/2" are preassembled. The third type is a genisis disk that is bigger still and, as far as I know, only works on genisis valves. I believe that the burst disk kits retail for about $4.

Tim