Uniform dilations modulo a prime

For p prime and 0<\epsilon<1, let k(\epsilon,p) be the minimal integer k such that for any set X of k distinct rationals in [0,1) with the same denominator p, there exists an \epsilon-dense dilation nX \mod 1
How does k(\epsilon,p) grow when \epsilon decreases? The best bounds known [1] are 
\frac{c}{\epsilon}  \log (1/\epsilon) \log \log \log(1/\epsilon) \le k(\epsilon,p) \le \frac{C}{\epsilon^2}.
 

REFERENCES

[1] Alon, Noga, and Yuval Peres. "Uniform dilations.Geometric & Functional Analysis GAFA 2 (1992): 1-28.

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