Perfect rhymes:
* Walker
* Stalker
* Balker
* Salker (not a common name, but it rhymes!)
Near rhymes (not perfect, but close):
* Yorker
* Barker
* Parker
* Swarmer
* Sharer
* Fiddler
* Ponderer
* Brawler
* Caller
Let me know if you'd like more options!