Re: Climbing the mast
I'll second Marcusc130.
PS reviewed several systems a year or 2 back and one of their highly-rated climbing harnesses was a Petzl rock climbing harness with stainless steel hardware for a couple hundred bucks. I bought a mid-range Petzl rock climbing harness at EMS on sale for $60. It has anodized hardware. As long as I don't store it in brine I figure it will last only about 190 years, instead of 200. I'll take the risk.
The whole rig, including 3/8" utility line, some webbing and anodized locking carabiners, was less than $100. I go up my 40' mast quite easily without any assistance from the deck.
The sit-harness is adequately comfortable for the kinds of jobs I've had to do up there. I don't think you need to spring for equipment made, and priced, for the boat market. Rock climbing gear is just as reliable, and people use it in salty coastal areas just as they do inland. Just make sure your halyards are up to the job. Having faith in your gear makes mast climbing pretty stress-free.
One tip--if you make web slings for your feet, join them with about a foot of webbing, so your feet stay beside the mast.