This one cost 50p,and has been up there for nearly a decade.
Seriously though these a piece of cake to make on a budget.
Charity shops are a good starting point.
You can find smaller ready made frames with flowers,or shells,etc..For next to nothing ,second hand of course.
Another option is get hold of a second hand picture with a reasonable frame. Ditch the picture keep the back panel frame and glass.
Then you just make a square to the depth you require using the back board as a template. (it fits the picture frame so as long as you don't go further than the edge of the backing board then the square frame you make will fit the picture frame no issues.)
In short with a quick trawl of the second hand store etc. You can DIY a decent one for $20-$30, and probably have plenty of beer tokens left over.
Mark.