<human>: My trouble is specifically with a groomsman, though I bet some ladies could use some help with bridesmaids.

For the wedding, I'd like--after consulting with the groomsmen--to have everyone in dark brown dress slacks, a lighter brown vest, and a dress shirt for less than $200. I'm trying to source everything, but sizing's become an issue for one of my groomsmen.

We love him to death and he's a great guy, though a little depressed atm, but he's... large. Very large. I'm worried about finding him a vest that'll fit while match everyone else's.

And then, he's reluctant to tell me his current sizing (which I know he knows, because he's also in the wedding party for a mutual friend of ours). He says he wants to "lose weight" before the wedding--which is all well and good, but we won't be getting stuff tailored until 2 months or so before the wedding, including me. I don't want to wait until the last minute to order stuff. (It's almost April, and the wedding's in October. That gives me 6 months.)

So! I suppose my question is two fold. One, when do I get the groomsmen to order their clothes in time for the wedding? And two, how do I gracefully/tactfully/successfully clothe my bigger, potentially too-optimistic groomsmen? (I say this only because we've seen him "diet" before and it doesn't really work.)

Can you summarize the given text in a few sentences?
<bot>: Bigger groomsmen is evasive with size, am fretting about getting him clothes that actually fit. Would like to know how others have dealt with similar issues.