Simpson Lawrence toilet? Wow!
They've never been distributed in the US...first one I've even heard of. I had to do a search to find out S-L even makes toilets! S-L's website seems to be under construction right now. However, if you do a google search using keywords "simpson-lawrence toilets," you'll come up with several UK distributors for 'em. But I don't have a clue where you can find parts for it in the US. As for your bladder tank, it may NOT vented...some bladders, especially in European installations, aren't. That may be ok for water and diesel, but if yours isn't I strongly recommend that you vent it. Waste produces gasses as it breaks down that expand, and bladders are notorious for blowing out fittings if they become even slightly pressurized. Besides, because methane is flammable, CG regs require all holding tanks in US waters to be vented to the outside of the boat...your boat won't pass an inspection if the holding tank isn't vented. If the toilet needs much work, unless you can find a US or Canadian source for parts at a cost well below $120, including venting the tank if necessary...on a 23' boat I'd pull the whole "shootin' match" out and replace it with a pumpable 5-6 gallon portapotty. No intake thru-hull, no intake seawater odors, no hoses to permeate, no bladder occupying valuable storage space AND "perfuming" everything in the storage locker it occupies... That's just my $.02 worth...it's your boat.
