The MXR Phaser has different variants, and here’s one. The Phaser 90 from MXR. There’s not much more to add appart from the fact thatit uses a more complex circuit with LM741 ICs, 2N5952, 2N4125, 2N3906 transistors. You can use many types of ICs such as the TL061. I am not going to list all the substitues,but you check, maybe you have one that fits.