Tolex is a vinyl, and not need the same care and cream/oil used for real leather. There are some products to use for plastic that are good for tolex.
I use this https://www.innotec.eu/oth/en/products/multi-spray-1000/p1205
I have a Marshall cab with 8 ohm V30, and is really close to the Mesa OS of my friend; mine is straight his Mesa is slant. Lynch not use his signature speakers?