Need help finding a low cost hardware firewall device

I am sharing part of my network with a third party.

The third party is connected to my hub, which allows access to the
internet.

We are connected externally via a Netgear broadband router.

I am looking for a low cost hardware firewall device which will enable
me to prevent unauthorized traffic between my half of the network and
the third party, which is on my side of the router.

I want to be able to selectively block traffic by port, type, ip, mac
address, in either direction.

I do not want a software solution.

Thanks in advance for any advise given.

SonicWall and Checkpoint now has a mini firewall appliance for small
networks. I'm sure you can get both on ebay.

You can buy the NETGEAR firewall router. I think you have NETGEAR
router using in home but I'm sure you can do what you mentioned with
NETGEAR Firewall router.

Sorry for my bad English.
Thanks