Huf as proprietor

Yes, Huf can be proprietor

HUF cannot render professional services.

Professional services are occupations in the service sector requiring special training in the arts or sciences. Some professional services require holding professional licenses such as architects, accountants, engineers, doctors and lawyers.

Please evaluate if Financial services fall under any of this category

Since HUF is one person as per Income Tax Act,
a Proprietor of a business can be an Individual or a HUF. 
A Proprietorship concern is Not Governed by any Specific Law as such,
and therefore there is No Bar on HUF becoming a Proprietor of any concern.

Some services are personalized services.Some services may not be personalized service. Ttarget='_blank' rel='nofollow' hrefore, income from personalized service can not be attributed to HUF income.
E.g.Sevices of doctor are in the nature of personalized services. I think you can not apportion you income to HUF income. However, a clinic may be run by HUF. From the income of the clinic you may draw some amount towards your personalized service. The income of clinic own by HUF would continue to be taxed in the hands of HUF.
So as you have to evaluate that things before any decision.