Mike,
When I shoot comps requiring weak-hand shots I find it's not too dificult using the "wrong" eye, it just requires the head turned to bring the eye into alignment on the sights, it feels a bit wierd but does work OK.
You could ask this fella -

http://www.airgunbbs.com/showthread....-Gammo-compact

if he might part with the L/H grips.

If you're stuck drop me a PM, I might be able to sort you out a functional L/H grip as I have a compact to work from,
ATB,
Nick