I would sure read the sheath on the cable to be sure, but it sounds more and more like you are using 62.5 nm multimode fiber. I really recommend a pair of Transition Networks SGFEB1024-120 for that. They are pricey, $1800 USD each.
If it is 50 nm and you liked the DLinks, they make a DMC-700SC that will do gig for 550 meters. $280 USD each is more reasonable, but they would only go 220 meters on 62.5 nm fiber so be sure you have 50 nm.
I tried to remain child-like, all I acheived was childish.