Theres at least a 1/2 dozen Scale guys affiliated with MMEU(http://mmeu.com/)with FE Scales, were a NAMBA club but do attend London FE events that offer FE Scale.
MMEU hosts the annual `Michigan Cup Race' that offers Scale however this year(because of pond size limits)our big race this year is centered around P-Power limits. The P-Shootout is coming up in 2 weeks.
Next year were hoping to go back to a larger format and offer FE Scale.
I believe if you set it up for IMPBA power requirements it should conform to NAMBA rules. NAMBA just laxed their Scale power requirements,IMPBA states certain motors.