Chub Rock
I'm honoured that you would use a photo of me. I would say if you can not find a kilt jacket then a conversion may well be the ticket here. I would definitely wear a jacket to the function. Please convey my congratulations to your wife. By the way the jacket I'm wearing in that photo is from Hector Russell and was an ex rental, perhaps you could find something similar.

As for hose I'd go for a pair that pick up one of the colours of your tartan.