Selection of sliding bearings with ultra-high load capacity

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Dear experts: I am working on the design of a heavy-duty transmission mechanism, specifically an eccentric cam linkage system. I am facing difficulties in selecting the appropriate copper bushings for the large and small ends of the connecting rods, and I hope you can offer me some help. The compressive pressure on the copper bushings is p=8.5 MPa, and the linear velocity is v=8.44 m/s; thus, pv=71.7 MPa·m/s. According to available data, the allowable values for materials used in sliding bearings are not sufficient to meet this requirement. For example, as stated in “Mechanical Design Handbook, Volume 2, Pages 7–8, Chemical Industry Press”: for ZCuZn10P1, the allowable values are 15 MPa for pressure and 10 m/s for velocity, resulting in a pv value of 15 MPa·m/s; for ZQAl9-4, the values are 30 MPa for pressure, 8 m/s for velocity, giving a pv value of 60 MPa·m/s. Similarly, for ZCuPb30 and ZCuPb10Sn10, the allowable pv values are also 60 MPa·m/s. Of course, I could adjust the design by reducing the diameter of the bearings in order to lower the linear velocity, but this would increase the specific pressure. Since the overall dimensions must be considered, the width of the bearings cannot be increased any further. Is there a better bearing bush material? Or the aforementioned materials can be used; it’s just that the allowable values specified in the manual are too conservative – can they be exceeded? Thank you for your advice.