Offer was genuine mate.
As for clothing - don't buy stuff online off the peg. From what I've heard (and seen) it will have to be custom fitted to you. Just need to look at some BBC documentaries for badly fitting medieval clothing - hose that's baggy, pourpoints that look like a child's waistcoat stretched over a full grown adult, linen shirts that are bleached white... All of that stuff will (apparently) be turned down at the gate.
Chrissie Carnie is a superb medieval seamstress so she's worth talking to. As is Sarah Thursfield. There arent many shops that will do a good job, as you'll just end up looking like a reenactor. Tricky though, as its probably only gonna be used once, but you wanna do it right....
Buy shoes first. You can get cheap nasty plasticy thin medieval boots that all look the same and won't last 5 minutes in wet mud, or stunning hand made medieval ankle boots based on existing finds that will last a lifetime. They'll look good at other shoots, too.