I too used to have a walnut stocked air arms 410 carbine.
Left handed stock , right handed action , with a w.t.c. on top .
Damn I wish I'd never sold it !
Traded it in for a HW100 when the first quckfill ones came out.
Then a left handed BSA R10 , then a lefthanded Daystate Huntsman and then back to a HW100.
B.A.R still list left handed Air Arms on their website as well as Daystates.