Here's Briley's selection of chokes for most Remington models - range is price from $ 18 - $ 75 ( on high end for a ported choke, which I don't personally recommend). Extened chokes are nice - but not mandatory either. I would opt for a middle of the road model of choke around $45 probably if I was buying them from Briley.
http://www.briley.com/index.asp?Page...TS&Category=35