Welcome to the site and thank you for your service to our country.
Only things available for your truck is the 4" Superlift suspension lift and the 3" PA(Performance Accessories) bodylift. I've got both on mine and running 35" tires.
As far as places to purchase, there's tons of places. I'd hate to suggest them, but 4wheelparts carries both lifts.
'01 XLT disguised as a '03 Fx4 Level II.