Heat Pumps and Electric Heating - ruud gas pack problem

Hello to all: I have a ruud gas pack unit at the end of my house, a 3.5 ton unit with i beleive 100,000 btu gas burner inside. The air conditioning part still works ok, but have had it worked on 2 or 3 times. Wire burned off the compressor 1 time at the little terminal stub, from vibration i think he said. The problem is the heat part is all rusted and the burners look like they have had it. The unit is 15 yrs old, and i didn't even use the heating section last winter because i have an outside wood heat system. My question is can i switch the unit out to a heat pump system, if so can i do this myself since i have been in construction and around this type stuff for 35 yrs, and have done my on coil cleaning and minor maintenance. Can i get a heat pump already charged with freon so all have to do is make the trunk line hook-ups and the wiring...What would be good quality system but not the most expensive. Thanks to all for your help....Oren

Most all brands have a package heatpump that you can put in that way.Trane has one WCY42
With a Seer of 13.05 and a HSPF 7.8 .Thats top and they go on down from there.

ED;)