I'm not trying to dissuade you from buying from LBS, and they can certainly help you with fit, but you're playing a pretty hefty premium for that. If you're okay with that, then great.

I think MTB shoes and pedals are fine for you, especially if you do any kind of walking on them. May not be as light, but way more versatile. I wear both and there's not much difference in the on-bike performance.