The stock guard rough riders used their standard horses (no barding, no caparisons) of the time, still of a rough size to the
WHFB horses last time they made them (don't know if they still do).
I used old VOID (1.0) viperwing bikes for mine, and they just fit onto the 25x50 cav bases (centre wheel to centre wheel) - and fit with a few
mm to spare front and back on the 70mm capsule bike bases. The ramshackle bikes aren't a lot bigger than the scout bikes from what I've seen.
Mogul Kamir is in the centre, on a modified scout bike (the fairing is the canopy bits from an old Mirage fighter plane.)