I think your essential conflict is the desire for a wide aperture, no need for bokeh performance and $300 price limit - IF - you want an SMC Pentax lens. Otherwise I'd suggest the K28/3.5. It is highly rated for sharpness and costs between $129 and $169 depending on who is selling. Some say the K35/3.5 is the sharpest MF lens Pentax ever made - I know I like it. The K24/2.8 is contrasty and sharp. But
f/2.8 and
f/3.5 won't do.
The M35/2 might be an answer but they're not especially common.
There's always the whole series of Vivitar Wide Angles, especially the 24/2 and 28/2. Pay attention to the Close Focus versions and look for Kiron and Komine as underlying manufacturers. When you see them they are generally under your price limit. sometimes by a lot. In K-mount alone there must be 25 or more variants of the 28. Somewhere around here there's a thousand-Post thread on them. I'll try to find it and come back and edit this post.
[EDIT:]
Here's a link to a Search I did that returns three threads from 2008 and 2009 on the Vivitars.
Good Hunting!
Vivitar 28"s
The "FA31 replacement" thread done by Robin Parmar resulted in an actual classification system for the Close Focus Vivitars. For a time here they were cult lenses.
Stevebrot's thread is a detailed analysis of the K02 variant.
I suggest you may find your solution in the Kiron/Komine Vivitar 28's!!