OP's current truck has a 5.5' bed. There is no camper out there designed to fit such a short bed. The truck carries a "no campers" recommendation.
Mainly, the rear axle is very close to the front of the bed, which makes it difficult to get the CG right on the camper without resorting to stacking lead ingots in the cabover.
He's right to consider a 35-series SRW. Problem being, a extended cab short bed 35-series truck may not exist. The big three have not offered that configuration in years past, though they may now. Extended cab, short bed has always been the realm of 25-series (i.e. 3/4 ton) trucks.
There are plenty of choices in short bed campers. All major manufacturers offer one. You will be limited to 8.5' to 9' of floor length, though, and even then you will be hanging off the back by 3'.
I dunno about parallel parking in a normal town/city situation... It sure won't fit in a normal space, and people might take exception to you taking up two if they're marked. Out in the country, go for it.
