Last night I was looking a the Swineshead site and decided to throw them an email to see if they were planning on doing a 7 string version of their SH90 (a humbucker sized P90). This is the reply I got:
Looking at the link they also are starting to do several other single coils for 7-strings, they also are available in lots of colours (no word on the wooden versions yet).
Planning to get a SH97 in glow-in-the-dark for the neck of my S7320 tomorrow, will report back on how it sounds and hopefully get a couple of clips as well.