Low cost 978 UAT Antennas?

The FA 978 UAT antenna is off the market.
DPD’s UAT antenna is ~$170 shipped.
Are there any lower cost base station outdoor UAT antennas?
I might need a few shortly.

I am planning to use a modified version of Cantena - lambda/4 is 77mm instead of 67mm.
Or try one of those cellular booster antennas for GSM 900MHz (EU frequency, not US) - the bandwidth is up to 960MHz, close enough of 978MHz.

In this case, I’m looking for a turn key solution for professional installations at some FBOs.