I assume you are on a tight budget
, otherwise you would just hand over the plastic at West Marine
Used anchors are just fine. Do not know of anyone that has ever worn one out. Do not think I have ever bought a new anchor of any size. Chain will lose its galvanizing, but not its strength with time.
I am in Sanibel, a couple hours drive south of St Pete. I have a 35 lb CQR
(brand name) I will sell for $75 if you want to pick it up. It is not pretty, painted and rusty at the tip, but does the job.
Look on craigslist, you might search by brand (eg CQR
or Bruce), otherwise you will find a zillion bass boat size anchors.