Parkster said..
Does anyone know a supplier of a good mast boot to fit a mast that is 23inches circumference. Mast is stepped already old boot is perished

It is quite easy to make one. Use a piece of inflatable boat material cut to shape (conical), wrap around mast upside down and stitch the joining edges together at the back of the mast. Position the top then clamp it to the mast with a bandit strap (stainless of course). Pull the boot over the top down to the deck flange/spigot and bandit strap the boot to that. Use silicon sealant at appropriate points to complete seal.

Some images here to assist. www.google.com.au/search?q=mast+boot&rlz=1C1NOOH_enAU504AU510&espv=2&biw=1366&bih=639&tbm=isch&imgil=7zMIo-rUoa2t6M%253A%253BLysaJ1hQrgfCWM%253Bhttp%25253A%25252F%25252Fwww.ericsonyachts.org%25252Finfoexchange%25252Fshowthread.php%25253F8626-Mast-boot-replacement&source=iu&pf=m&fir=7zMIo-rUoa2t6M%253A%252CLysaJ1hQrgfCWM%252C_&usg=__HYjZQ8jSrk_uJwke-mC7egykoo0%3D&ved=0CCYQyjc&ei=8O50VYPqAsXcmgXhxoLoCA#imgrc=7zMIo-rUoa2t6M%253A%3BLysaJ1hQrgfCWM%3Bhttp%253A%252F%252Fwww.ericsonyachts.org%252Finfoexchange%252Fattachment.php%253Fattachmentid%253D6473%2526stc%253D1%2526d%253D1269999334%3Bhttp%253A%252F%252Fwww.ericsonyachts.org%252Finfoexchange%252Fshowthread.php%253F8626-Mast-boot-replacement%3B800%3B600