flange-less right hand cup - (adjustable 'fixed cup') BB ?

i've got a BB (BSC cup and cone style) i've got to fix

• the RH cup has come out fine, the left will not budge - i'm considering using the right hand side as the adjustable side (effectively using the stuck left cup as the fixed cup now )
  
  

technically it will work no problem - (the conventional set of fixed cup onthe right is just that - a convention), but the availability of parts to do it might be the problem,

i've seen cartridge style BBs that have both cups as adjustable
for eg. this :
http://www.spacycles.co.uk/products.php?plid=m2b34s110p148)

• i have one of these and could take the reverse thread lockring off it if need be -
  
  

the real problem is finding a RH flangless cup that will protrude enough when set for me to attach the lockring- does such a thing exist as a problem solver or just as a standard part of an existing cup and cone BB?

i'll continue to try to remove the intransigent LH cup - and look into the possibility of grinding a flange off an existing RH bb cup and thread locking / grub screwing it in to keep it tight .
i'm just hoping a part might be out there to sort this with no further ado .

cheers