I am looking for an affordable industry M2M LTE/UMTS router with IPsec support and OpenWRT.
Until now, I use the "LR77-v2" from Lucom (not with OpenWRT), but it is too expensive for a product, which costs only 3000€. I have found this:
But I think it would be even cheaper with less equipment.
You might also want to consider an approach like a PC Engines APU3C4 (the "3" variant is tailored to support of LTE modems with dual-SIM support and more robust mounting of mPCIe cards) and a mPCIe modem from a reputable vendor. With, for example, a new Sierra Wireless modem from a mainstream, commercial supplier (Future Electronics, Digikey, ...), a 16 GB mSATA drive, pigtails, power supply, and case, single-unit pricing is around US $300-350.