Yes, the candidates will be members of Scottish Labour, hence why they'll brand themselves as that on the ballot paper. However they're standing to be elected for the wider UK party in the HoC. The manifesto released during the week is a UK-wide manifesto, and given time constraints I'd imagine it's unlikely there'll be a specific Scottish one.
Don't get me wrong, the state of Scottish Labour and their staunch, obsessed stance against independence that they never fail to remind us of whenever they receive airtime is still the main thing that puts me off voting for the wider UK party, but I also find it very hard to disagree with much that has been put forward by Corbyn, independence aside.