I have not found any fruit puree similar to the Oregon brand purees, unfortunately. But I can recommed the BrewHouse Prairie Wheat kit. It gets great reviews, and I have had outstanding success with their other kits.
Based on the quality of their other kits, the FestaBrew wheat beer is probably very good, too (although a bit pricier).
I have never had any real success with the Coopers, Muntons, Baron's or Morgan's kits. Compared to the Brewhouse and FestaBrew all-grain kits, everything else is pretty marginal, IMO.