OP,
Best is to get the Dish 1000+ and a DPP44 switch.
The only difference between the Dish 1000+ and 500+ is that extra LNBF for 129 on the 1000+. But you have to use the DPP44 switch with the 1000+
Check with DN if you can get an upgrade for your dish with little out of pocket money. They may ask you to extend your contract time.
If you want to buy your own dish 1000+ and DPP44 switch, check our page here:
Dish Network satellite dishes Winegard KTI jonsa
Is there any benefit to getting 129?