No need to worry man. My guess is that bar's leak you put in temporarily screwed with the oil sender, or the oil sender is just going bad. I had mine go just last year. I was driving and suddenly the check gages light came on, had zero oil pressure, I parked it, and when I came back to get it, everything was the fine, almost the exact same circumstance. Replace the oil sending unit and change the oil to get that bars leak out of there and you'll be fine.
<img src="/forums/images/graemlins/smile.gif" alt="" /> as far as your radiator, do it yourself. the estimate sounds alittle high but not to bad. You're paing for labor, and it's not hard at all to do. your oil pump and crankshaft seal both require the removal of the oil pan. big job to do if the motor is in the truck. Most of the cost of the job is labor. I don't think you need it done though. Oil pump is either good or it's not, if you got pressure, it's good leave it alone. your oil leak, all wrangler owners have got crankshaft oil leaks. I've replaced my seals twice on 2 different 4.0L's and still have leaks. the repairs only hold for 5-7K miles. don't worry about it, drive it---I mean wheel it.