Try a gig case; I got one for by boy’s electric guitar. Basically it’s a hard shell rectangular box NOT shaped for an instrument. The one I got cost about £30 maybe £40 I’m not sure it was some years ago but I think it would have been big enough to meet your needs. Width at least would be no problem for the two guns. It’s only drawback as I remember it was weight, lots of weight but it offered excellent protection for its contents.

Regards Ora