I've met a few who do.
It is a very small market and difficult to quantify.
There are the more specialised 'tantric' providers who will include orgasm as part of the regime for women clients. The provider may be male or female. The whole subject of tantric massage is very complex. Tantric providers are not huge in number and are often concentrated in larger towns in particular the capital.
In terms of the 'high street' massage providers where happy endings may be on the menu (and are frequently reviewed on here), then inevitably some will have a small number of female clients, who are also seeking 'an ending'. However the overall numbers are small and many providers will therefore have none, as a result of either lack of demand or by choice.
Choice is also an important consideration for the client, in terms of preference for a male or female provider.
Indeed many women are likely to be put off seeking even just a massage, from a provider who spends much of her day wanking off men .. or worse

The other issue is that, in general terms, successfully providing a happy ending to most men is not an unduly onerous or indeed a time consuming task. The same is not true for the majority of women.
As I have posted before in relation to this subject then the potential market is probably much greater, but for a prospective female seeker of such a service, finding a provider (be it a male or female) who possesses the required skill set is not easy. As a result there is a lot of 'word of mouth' involved in finding and choosing one to make the financial outlay worth it.
Also being an experienced, skilled and qualified massage therapist, does not equate to being skilled with ensuring a satisfactory female orgasm. The latter is hugely more variable and complicated and can require a natural aptitude and many years of experience with a wide range of women to perfect.