There's a guy that does an SMS to web gateway with real telephony hardware. You pay by bitcoin and its accessible over TOR. You pay, he pops in a topped up PAYG

There's a guy that does an SMS to web gateway with real telephony hardware. You pay by bitcoin and its accessible over TOR. You pay, he pops in a topped up PAYG SIM. You have a real mobile telephone number. You can run your own private one at home with a Raspberry Pi/ttl serial adapter and a cheap SIM module. Or use a dongle.