I work in a similar sized company that manufactures kitchen and bath counter tops and has retail kitchen and bath design showrooms. I'm the only IT worker there, and I work there part time. Well, part time is kind of a misnomer, I work there whenever there is a problem, or whenever I want. That being said, I work about 20 - 30 hours a week on average. I'm responsible for about 45 desktops and 3 servers spread out over 7 locations. We have 3 owners of the company who are the CEO, CFO, and President. My boss is the controller and he works under CFO. Basically the only time I have to go to my boss is when I want to make a company wide policy change, or if I need some money to order parts.
TL~DR Your boss should be someone with purchasing authority.