wanted: Speedometer cable for 1984 B2000

We have a 1984 Mazda B2000, 4 cyl, 5 speed, 2wd. Our speedometer cable is leaking oil, into the cluster, causing our speed-o to fail.

Our local mechanic told us we need a new/different speedometer cable with a good housing (they aren't listed as an available new part).

So, I am looking for a good, used Speedometer cable, and perhaps dash cluster for a 1984 Mazda B2000.

Also, would any one know if a speedometer cable off a newer year truck (1985 - 1990 ) would fit on our 1984?

thanks much