My experience is that TekTelic have received a lot of enquiries for their solutions and are playing ‘catch-up’ on the orders.
If you contact them directly, the team can give you an update and costs.
I’ve seen some informal test results for their indoor LoRaWAN gateway and it’s performed better than the Multitech gateways. Unlike other devices, this isn’t built on a Linux platform. It’s all in the chipset, which means - other than a small configuration file - it’s plug and play. This may or may not be a good idea for your solution.
Regarding availability: In fairness, with the exception of MultiTech and Kerlink, several gateway companies we work with are struggling to fill orders. The easily configurable Laird Sentrius is on backorder with delays of up to 8 weeks here in the UK.