Thanks Shelagh, I'll keep you posted.
This marriage is actually 4 years after what I think is the baptism of "their" first child back in Kendal. I know from the baptism of "their" son John in 1750 that he was the son of Richard and Jane, and this is the only marriage I can find that seems likely - i.e. the correct names, more or less the right time & they're described as from Kendal and nearby Strickland Roger respectively.
I thought it possible that they'd go to Sedbergh to marry if they'd already been living 'in sin' and had a couple of children. But, as I said before, it's entirely possible that it has absolutely nothing to do with my couple at all!

I'd just like to get to the bottom of it all!
Jill