Sorry about your troubles
From someone who does automotive ac work on a daily basis.
#1 if the seal is leaking a little now (add a can every week), within a few months (or days-you never know)it will be a can a day or worse. Fix the problem.
#2 if the seal is leaking than there is no need to flush the system, its a leak not a mechanical component failure that will send contaminants into the system.
#3 go with an OE compressor. Auto zone or oriellys reman. Compressors may sound great as they are cheaper, but we have had some that would not make it out of the shop doors without failing, and then your doing it again. And as much as most dealers charge for labor at $100+ an hour, I would only want to pay it once.
I hate to justify a cost cause I dont want to upset anybody, but brake down the cost.
$500 for ac compressor
$10-20 for orifice tube and oil
$30 at $12 a pound most have around 2-3 pounds for larger vehicles
$180- labor for evac and recharge. Book time for all smaller automotive systems is 1.8 hours
+2-4 hours @$100hr for compressor install its self- I dont know what book time would be on this. Of course the harder the access the more it will cost. I can see how $1,000 would be easy to hit.
- I did one on my little sisters sunfire and compessor, new line (about $45)(there was a rubbed area on the line) freon and oil, and I had about $450 in it and that was me getting employee- 10% over cost on parts & no labor.
Just a little perspective, not trying to ruffle any feathers
Edit-ps. I have never heard of any shop that will re-seal a compressor or any aftermarkets that do a real great job of it consistently.