In your case maybe a light duty dock would be fine, how much of a cost savings that equates to is unknown.
Guess you won't know for sure unless you call around and get some prices.
Now if you were really looking for a deal just go buy yourself a few old snowmobile trailers off craigslist and make your own dock. I bet you could even make some custom bumpers from your extensive noodle collection. Just think of the possibilities - you'd have a dock that would be the envy of all your neighbors.