don't have a K 1 but I use a Joby Ultrafit Hand Strap and Ultra Plate:
" Hand strap and universal baseplate for DSLR cameras
Comfortable, lightweight strap conforms to hand for solid grip
UltraFit Layered-Pad Technology™ provides support without bulk
Integrated UltraPlate baseplate is Arca-Swiss compatible
Versatile baseplate includes two 1/4''-20 attachment points
Supports sling strap or other camera accessory "
https://joby.com/us-en/ultrafit-hand-strap-with-ultraplate-jb01277-bww/
don't know why that wouldn't work with a K 1