help regarding circuit

hello every one. i am not much related to electronics But still want to build some small interesting projects. And now i found a project on **broken link removed** and i am very much qurious to build it But few things teasing me that

1-which hall effect sensor should be used? can any one tell me the part number so that i can purchase it.

2- I am unable to find TX-2B IR ENCODER and RX-2B IR DECODER ICs. can some one please tell me any alternatives of these ICs. please

Melexis Hall Effect sensors:

i have no idea which one to choose. please help me and tell me.

I think MLX90217 is used in this project. this is what i THINK. But i want YOU to check out and please tell me am i wrong or right? and please prescribe me with the right Sensor Please. And please tell me an opto-coupler (with part Number), if i want to replace the sensor with this opto-copler, so i could easily replace it.

and thanks for your reply

Isn't there anyone,who can help me on this?

Here is the .pdf