stand that goes LOW

[Three Valves]

I wouldn't cut up the tuba but I'd consider mounting an adjustable stick to it like this one...



(Borrowed from Frankentuba)

[MikeW]

1 - higher chair: I have a fold-flat chair from IKEA on which the seat is 25" high, with a footrest (as opposed to 17" for a regular chair)

2 - cheap, ugly, but said to work: an up-turned plastic bucket or sturdy flower pot

3 - the "steward" stand; like the spike on a cello, but attaches to two bows on the tuba. Not sure if it uses metal clamps or softer straps. I have seen posts about one or two of these that have been soldered to the instrument.
The standard model is intended to support the instrument on the chair, but apparently a longer leg can be substituted to support it at floor level (add a rubber "cane tip" to prevent slips)

4 - I have seen posts that suggest a piece of 1" broomstick dowel, with some webbing and velcro.

[Three Valves]

You can borrow one from the trombone section...