Unfortunately in humanities subjects it is very difficult to get onto a PhD without a Masters, especially when applying for PhD funding which is very competitive and unfortunately decreasing (I'm not in Philosophy, but am a PhD student in another humanities subject). Often when the entry requirements are ambiguous regarding whether you actually need a Masters degree, they mean that people with extensive work experience in that area may be able to progress straight onto a PhD.
If your proposed project falls within it's remit, the ESRC doctoral scholarships can include a Masters degree in their 1+3 award, so you'd get funding for a year long masters degree and three years for the PhD. The AHRC unfortunately don't offer Masters funding, as far as I'm aware, so this would depend on which funding body your project falls within the remit of. You may find that some university department have scholarships of their own for Masters degrees, and even if they are announced after the deadline for accepting your place, I'd still recommend going for them. Even if you accept a place on a Masters course, you are still able to either withdraw it or defer for the next year (at most universities, I've heard some don't allow deferrals). They can't force you to actually go forward with the Masters.
You may also want to consider a MRes/Masters by Research - these are, at my institution anyway, about half of the price of a taught Masters degree. You can also normally do any taught or research Masters part-time to spread the costs and allow you to work alongside it. Still expensive of course, but this may be an option. Also keep in mind that some universities charge higher tuition fees for their Masters degrees (I believe Oxford and Cambridge do), so if you're not set on going to a certain university for your Masters you may be able to find more affordable options.