I would say you are a VERY lucky man because not only did you win yourself a fine new rifle but it's chambered in one of, if not, the most accurate rounds you can buy over the counter.
The 6.5-284 was a wildcat based, obviously, off of a necked down 284 and it's probably the easiest wildcat, back before Norma and Lapua started making 6.5-284 brass, ever made. Not only was it a very easy wildcat to make but they were easy to make shoot extremely well with a wide variety of bullets and powders, both of which lead to its popularity.
The 6.5mm/.264 bullets, especially in the 140gr. range, have exceptional BC's and SD's and for a mid range caliber that doesn't shoot an excessive amount of powder and has a mild recoil level, IMO, it doesn't get any better than the 6.5-284.
As you've already found out, finding factory ammo, depending on where you live and the stores you go to, will certainly be more challenging. If you already load your own for other guns you'll have no problem loading your own for this one and loading your own will not only be cheaper but will give you the flexibility to use whatever bullet/powder/primer combo you choose.
I've got a 6-284 that is the little brother of the 6.5-284 and it's a coyote killing machine but if the action I used for my 6-284 build had been a long instead of a short, it would have been a 6.5-284.
Congrats again on your WIN!! Now get that thing scoped up and get it to the range so you can report back how it shoots.
