$5500 is a lot of money for a 2010 crawler/loader. That is unless it had been all gone-through and in excellent condition. When it comes to the "10" series crawlers, I'd rather have a gas engine. Some of the parts for the diesels are near impossible to get.
In my area of NY - a typical running "average" 2010 crawler would bring $1500-$3000. For $5500 (or less) you could buy the more modern 450 that took its place.
As someone else mentioned - 1010s and 2010s use "sleeve-decks" so sleeves are only changed all four at once. That in itself is no big deal. Who the heck rebuilds an engine without replacing all the sleeves anyway? Part prices and availability is the issue - especially with diesels.
2010 had a lot of Deere firsts. First full-size wet sleeve engine, first HL-R powershift transmission, and first diesel with a Stanadyne/Roosamaster rotary injection pump. The early 2010 diesels went through many quick upgrades and mods.