Hi,
2 x 250k audio pots are the standard values for a telecaster - which does not mean that you cannot use other values. E.g. I have a tele in which I use a 250k audio volume and a 500k audio push/pull tone pot. If I want the tone of a 250k tone pot I just turn down the 500k tone pot a bit. This works because the tone pot is just a capacitor connected to a variable resistor connected to ground.
In order to have a working tone pot you will need a cap. Usual values are between 0.01uf and 0.1uf - the larger the darker the tone gets when you turn the tone pot down.
But I guess you were asking if you need one at the volume pot as treble compensation (aka volume kit or treble bleed but I find the latter term rather misleading since these do not bleed treble away - they enhance it to compensate for the loss of treble when turning down the volume pot). Usual values are between 100pf and 1000pf - the bigger the brighter the tone gets when you turn down the volume pot. To compensate for excessive brightness when the pot is turned down, a resistor can be added in parallel to the cap (usual values for that range between 150k and 1meg) or in series with the cap (usual values are 150k to 330k). Fortunately caps and resistors are cheap, especially since you do not need large voltage handling capacities - 1/4 watt resistors and 6V caps are fine. For a 250k audio pot I would first go without a volume kit, then try a 220k in parallel with a 250pf cap. See what you like better.
Cheers Stephan
