Go ahead and pick up a nice female '06 '07 from somebody, invest the time to get it up to size... The chances of picking up an adult female gap are slim to none (you actually have a better chance of catching an adult female in my opinion), the only ones I know of that might be on the market have thrown all slugs for a couple of years in a row (not my animals, but not a good investment as a breeding project).
Now for the hard, but not impossible part is to pimp him out on a breeding loan to somebody that either needs a male, or who is interested in his genetics and work out some kind of split of offspring in advance. And also, one person or the other will be entrusting their animal out for at least a few weeks, I would work that out up front as well.
Lance