I am sorry, I have'nt seen anything. Most of the Mariachi costumes out there seem to be beyond your buget.
I would suggest go through your closet and see what you have, first.
What youy don't have, go to Goodwill or a vintage store and purchase any needed items like, pants, jacket, shirt, etc.....you could even do a vest, if you can't find a black jacket. Then go to JoAnn's and buy white appliques, silver brick-brack or metal buttons , some red material for a belt or a scarf.....to try to achieve your Mariachi.
The hat should be able to purchase or rent at a costume place.....
Here are some examples to give you some ideas. Good Luck! H1
A DIY Mariachi Costume- This webpage has quite a few pics to get some ideas. Oktoberfest2 2007
Hi, I made outfits similar to a Mariachi outfit to be worn for a mexican themed party. It started with one outfit and then the following year, I made 2 more to match (had to have the 3 amigos!). The hats I think would be the hardest to get for cheap. I had one hat, found one at a second hand store and the other I found on ebay. The rest was pretty inexpensive. Here are a couple pictures...sorry I don't have better ones. They were very easy to make. Would something like this be good enough?
I made flamenco costumes for props for a theme party last year. The guy had the short jacket. As was posted above, you can get items to modify at a thrift shop (Salvation Army, GoodWill, etc.) For the jacket, just find ones that fit the wearers, and cut off the bottom part appropriately and re-sew a bottom hem and embellish. You could maybe even stencil the designs with silver paint if you couldn't find trims to fit the budget.
I usually try to find clothing items that have some element(s) of what I want and then modify from there.