Hardware Firewall to work with Dual WAN Peplink Balance 20 that will still offload the balancing to the 20x?

I’m looking for a home office firewall device for ~ $200 to $400 USD that can accommodate my two IPs, which currently are setup like this:
I’m using outbound policies of Fastest Response, Enforced, Priority and Persistence. Depending on SSID when over WiFI, or IP or mac address for wired devices)

I would like to keep using the Peplink load balancing algorithms but have a full featured firewall in front of it to filter traffic of both ISP 1 and ISP 2. Suggestions?

So far, I’ve been looking at:

I’m leading towards the rack mount options.
1U Rackmount Network Appliance | 1U Rackmount Server. (considering)
Fortinet Firewall Appliance Rack Mount - 1U.

With random ware attacks on the risk. I think all offices, whether home-office or small office, should invest in robust firewall security.

Update, I’m going to go with this one:

I will most likely install pfSense on it (open to suggestions, prefer no yearly fees). I work from my home-office as such, it’s only wise to invest in a full-fledged firewall. There has been a rapid rise in ransomware attacks and other threats.

I’m also still considering trying Sophos.

Will try both for a week and then decide.