If for whatever reason you want to replace standard feet, here is a proposal for a home-made version.
Material:
- plank 10x68mm
- plank 25x46mm
- screw SPAX 4.5×60 T20 (1/foot)
- screw SPAX 3.5×35 Z2 (4/foot), or 4.0×35
With thicker plank cut pieces with an angle of 12° 12.3cm long (front), and pieces with an angle of 20° 12.8cm long (rear).
With thinner plank cut square pieces of 84mm long (1/foot). Drill 4 holes (diameter 3mm) 14mm from long boarder, centered in the other direction, with spacing: 55 & 34mm. Drill a 5th hole in the middle of the 4 other ones.
Tip: do not take 55/34mm as a given: I measured 62/34mm on another pair for example.