Convert Designs to High-Res

I have several finished designs sitting in PNG format, but the resolution is too low for my printer to accept them. I need each file rebuilt or up-scaled into crisp, print-ready artwork suitable for silk-screening and direct-to-garment tee-shirt production.

Here’s what I’m after:
• Recreate or vectorize the existing artwork so it holds sharp detail at 300 DPI (or higher) on an adult-size tee.
• Preserve the current look and proportions; if a size change would improve print quality, please advise me before proceeding.
• Provide final files in layered Adobe Illustrator (AI) or Photoshop (PSD) as well as flattened high-resolution PNG and PDF versions.
• Keep colors consistent with the originals so the finished shirts match what I already approved.

You’ll be working from my provided PNGs, so experience with Illustrator, Photoshop, or similar upscaling/vector tools is essential. A quick turnaround is appreciated, and clear communication on any limitations or improvements will help us wrap this up smoothly.