I have several domes on bird feeders. The domes I prefer (and have several of) I just can't justify spending the $30 each. I needed two more so I took a cue from several of the craftier folks in the forums and after a visit to Dollar Tree (bowls) and Lowe's (stainless steel hardware) I think I have roughly $5 each in these shown below. Green isn't my first choice but I broke the clear hard plastic bowl drilling it for hardware. Foresight led me to buy three bowls!
The hardware list is:
1/4" stainless steel eye bolts - I used 2" long and 2.5"...both still 1/4" diameter. I kept the nuts on them they came with to hold washers in place)
1/4" stainless steel coupling nuts
1/4" stainless steel washers (on both sides of bowl)
and I added some S-hooks I already had but you might not need those
The hardware was the most costly part of the ~$5 total.
If a bowl breaks, it's $1 to replace with the existing hardware.
The clear bowls are harder plastic (and brittle). The opaque bowls are more flexible.
Now I'm looking for appropriately sized bowls to use for my hummingbird feeder domes.