contact some of the parts sellers in swap shop, Im sure they have a couple, 115 bucks what a bargain..........

2 pipe tees and 6 nipples. 10 bucks at lowes. Little black paint...

I have that thermostat housing . Make sure you monitor you engine temp. Not just the thermostat housing. I had overheat problems last year . Fresh water pressure was dead heading hot water exiting engine through manifolds. The temp gage was reading around 140 but when I added a sender to the water cross over on the intake it was well over 200 just idling. Warped valves. wasn't happy . They were New engines. I modified my housings so all hot water exits out the transom separate from incoming fresh. The exhaust manifolds were not factory. Now the manifolds and engines both run cooler.

Sorry. I was referring to the pic grif posted