Bronze
 

Hi again,
If it's good bronze, and actual bronze (not brasses like manganese bronze or naval bronze), and if the scantlings are right, bronze is great.
Fair leads,
Brion Toss

Thanks Brion

The readily available bronze bushings are scinterd bronze:

86.3-90.5% copper
9.5-10.5% tin
1.0% iron
0% lead
1.7% carbon

No zinc which I think is a good thing for strength. But that one percent iron would seem to be problematic in the marine environment.

Also, SAE 660 bronze:

83% copper
7% tin
7% lead
3% zinc

for which it is said: The alloy is not subject to dezincification and has reasonable corrosion resistance to seawater and brine making it suitable for pump and valve components.

Thoughts?

Alloys
 

Hi again,
As I understand it, if it has zinc in it, it is brass. So let's eliminate that one. Iron isn't necessarily an obstacle; some of the strongest, most corrosion-proof bronzes contain iron (and other metals that you might think would be a problem), but through the magic of alloying all is well.
It looks like your other choice is a variant on something called "tin bronze", which is actually, you guessed it, a brass, even though it has no zinc. I don't know anything about how it might behave when turned into a bushing ...
Fair leads,
Brion Toss