Hi Paul,
I doubt very much that your problem is the shoes. I'm still using the originals!
At the handbrake lever check the "compensator" device for damage and that the cable adjustment is reasonable.
Remove the drum/disc assembly, clean out the brake dust and lightly lubricate the handbrake shoe pivots with suitable grease.
Check the disc thickness and the condition of the drum surface and renew if necessary (when I did this, my handbrake suddenly dramatically improved).
Refit and adjust the shoes following the traditional method rather than that in the manual (which is less than satisfactory).
Simon