You might be interested in the Monarch sold by Kollman Wings at the
websited below. I am not sure if it is a Marske approved design or
not but it looks similar.

http://www.kollmanwings.com/Home_Page.php

The Monarch is an open cockpit sailplane that tows with hang glider
equipment. It is well matched for scooter towing or air towing behind
trike or Dragonfly. It thermals well at speeeds hang glider pilots are
used to and has similar turn radius in thermals. The control system
uses standard stick and rudder 3-axis control.

The Monarch H is a redesign of the Monarch fuselage to allow for prop
clearance. This allows for a motor to be mounted behind the pilot
similar to a trike.
Monarch H specs
wingspan.........................43.5'
wing area........................165 ft sq
Best L/D ........................20 @ 35 mph
Minumun sink....................135 ft/min
Empty weight...................180 lb glider version...... 250 lb
motorized
pilot weight......................130 lb to 250 lb
Stall speed...................... 30 mph @ max weight
Vne.................................65 mph.

Monarch H kit............................................... ......
$9,500
Monarch H ready to fly.....................................$14,500