I agree with Shannon, I think the first thing you need to understand if what is the goal for the SWAG you are selling. If the goal is a secondary revenue stream, and you believe it can be consequential towards your bottom line, then you can do the following:
1. Do some quick research on other startups/tech companies that sell SWAG to see where the market is priced at.
2. Do some quick market research with a survey to existing customers or even a random set of potential customers using something like Google Surveys (https://marketingplatform.google.com/about/surveys/) to get a quick barometer of the price point that feels plausible
3. A/B test different price points to understand your demand curve and maximize profit
4. Likely a good idea to price slightly higher than your ideal price and then offer a discount
If instead you want to maximize the volume of SWAG sold to help evangelize your customer base and drive awareness/growth, then you don't want to maximize profit you want to maximize sales while staying within your acceptable cost scenario (may be comfortable losing a little money on each sale as a marketing cost, may want to be break even, etc.). You may even want to charge a premium for purchased SWAG to subsidize additional SWAG that you give to free to your highest profile customers or best evangelists. At my previous startup we used SWAG as a "user love" tool, giving out SWAG to our biggest fans or as a parting gift when customers visited our office.
If you'd like to chat more let me know!
Unlike what most people think, pricing is supposed to be based on value (not production costs). The value perceived by your customers (mainly), and the value that you give to your products/services and brand.
As with all new products or services, I suggest that you use AB testing (different sales pages with different prices) to see which price fits best.
One last thing to remember: even if you can charge more, doesn’t mean you should (that said, if you offer a quality product, don’t undersell it).
I’ve successfully helped over 300 entrepreneurs and would be happy to help you as well. Let me know if you need anything.
The question is what is more important regarding your swag. Is it profits, or is it brand recognition? As a budding business brand recognition can be equally as important as the revenue that the swag generates. If you want to get your brand out there, price it lower to potentially generate more volume and hypothetically greater brand recognition.