First off, apologies to op, i don't have a recommendation in the price range you are looking for.
$13 for 30 ml is not expensive though compared to other vendors. It's pretty close to the median price i'd say, and it's a price i am comfortable paying ( and i do ). The other vendors i buy from tend to be in a similar price range ( i buy when they have sales ). Affordable on the other hand is a subjective term. A student who vapes 300 ml a month has a very different budget compared to a well off retiree who vapes 50 ml a month.
I don't really agree with the " you get what you pay for " argument, at least not when it comes to eliquid. There is no criteria eliquid can objectively be judged on by different vapers, which results in the same ranking ( or similar even ). The cost of raw ingredients in a 30 ml juice is less than 20 cents, regardless of the quality. In fact the bottle and label cost a lot more. How you price you eliquid depends on a lot of variables ( your overhead, volume, marketing budget, business model, target audience, etc ... and above all, what you think the market will bear), but the cost of the ingredients in the eliquid, is not one of them. I have vaped liquids costing less than $ 10 per 30 ml, that i thought were far tastier than liquids costing $27 per 30 ml.
Op, there is no reason you shouldn't find tasty liquid ( to you ), at a price you are comfortable with. Worst case scenario, try diy. Loads of tried and tested recipes online, even if you don't have the time, skill or creativity to design your own liquid. My 2 cents.
