This is a classic case of trying to use an inappropriate connection method, I2C was designed for interconnecting IC's on the same PCB.
If the sensor is only available as I2C?, then simply use an 8 pin PIC (or other controller) to read the sensor via I2C and communicate back via a more suitable system.
My temperature/humidity sensors, while not I2C, do just that - they connect via a 16F1827 PIC to an HC-12 wireless module. Each module has an address (in my case just a single letter, but you could easily use more), and is read in turn by a PC program wirelessly, but the 'master' device could just as easily be a PIC or anything else.