i do have some spears/valves left over from my keggles mods. don't know the sizes, though. seems all of the kegs i've done have still held pressure and had at least 1/8 of beer left in e'm.
the craziest was the widmer that i got about a month and a half ago- guy bought the thing ten yrs ago in california and has hauled it across country thru 10 homes and it was 1/4 full and all pressured up.
Sometimes, I doubt your commitment to Sparkle Motion!