Decided to compile a list of repaints by third-party repainters for easy reference. If repainters would like to contribute here, do drop me a PM or drop a post with the link to your paint and I'll add it in:
747-400(PW):
747-400(RR):
747-400(GE):
747-400ER:
747-400M:
747-400D:
747-400F:
747-400BCF:
747-400ERF: