key-chains and pens might be your only problem when looking for a "one stop shop".
Most larger lines don't go to one place that does it all. They outsource the the specific businesses that fit their needs for that job.
The place that does the best job on pens, may not be the best place for keychains and both of those places probably aren't the best place to get t-shirts screen printed.
You can find screen printers in your area at PrinterListings.com that probably offer the relabeling and t-shirt printing services (even hats), but you may need to find a promotional products wholesaler to handle pens and key chain orders.
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