O.K.
That's not too small. I would imagine that the speakers would be on the one wall without windows? So, essentially you are working with a room DEPTH of 13 feet.
Most desirable would be a listening position three to four feet off of the "Back" wall, in turn leaving you with 9-10 feet for speaker positioning. I would suggest immediately a speaker that could be placed against the wall. That would allow you a little more versatility with your listening position.
Because of the size of the room, you may find a bookshelf speaker, even if very efficient, having a problem in a room of that configuration. With 70 watts, I would be concerned with speaker efficiency and would want something in the 89db efficiency rating minimum. I would try to avoid any type of subwoofer arrangement, so a floor standing speaker should provide enough bass reinforcement simply due to cabinetry and you would want to consider (if ported design), a front firing port as to not induce any additional wall excitation.
Considering your amplifier power and your posted listening preferences, you would want something with a fast articulate bass driver to help maintain transparency and minimize cabinetry interaction, and assuming the "other" considerations ie: clean power, quality interconnection, etc. have been addressed and are correct, do a little homework and investigate the Triangle line of speakers.
In particular, a speaker that might do a great job in a room like yours, is their "Heliade ES". 91db efficient, floor standing, front firing port, three way design, can be placed less than a foot from the wall, Stereophile "Class B" rated (for what that's worth), available new for less than what you're willing to spend. (about $700pr. from Upscale audio)
One word of caution.... A very revealing speaker. So if you are having problems upstream, they'll make you very aware of them. Otherwise, an awesome sounding speaker. They would be absolute heaven for Steely Dan and progressive jazz.
P.S. You'll need to do some room dampening!